The health risks to public from Japan's nuclear accident is no worse after a change in the disaster's status on Tuesday, the World Health Organization said.
"The risk assessment for health hasn't changed outside the 40 kilometres zone... outside the 40 kilometres zone we do not believe that the risk is greater today than it was yesterday," said Gregory Hartl, spokesman for the UN health agency.
Hartl also stressed that there is no one left in the exclusion zone, and that measures taken "appears to be enough" for the moment.
Japan upgraded its month-old nuclear emergency to a maximum seven on an international scale of atomic crises Tuesday, placing it on a par with the Chernobyl disaster a quarter-century ago.
The reassessment to a "major accident" with "widespread health and environmental effects" was based on the total radiation released, which officials said was one-tenth of the 1986 accident in the then Soviet Union.